Contact screw



April 2, 1929.

R. H, WlLLIAMS CONTACT SCREW Filed April 1927 INVENTOR 5 /1 M11 M/VSATTORNEYS I ply of current. a A further object of my invention is toprovide a device of the type described which is simplein construction,and eflicient for the Patented Apr. 2, 1929.

NETE s'rars masts arr Fries.

noy'nnnnimn WILLIAMS, or nvansvrnrn, INDIANA.

ioonracr sonnw.

Application filed Aprill, 1927. Serial -No.*180,265.

My invention relates to improvements in contact screws, and it consists1n the comb nations, constructions, and ar 'angements hereplace the fuseplug when blown resorts to the placing of a penny or a metal stripbetween the lower or central contact of the fuse plug and the centralcontact member of the fuse plug receptacle for securing a continuedsuppurpose intended. I

Other objects and advantages will appear in the following specification,and the novel features of the invention will be particularly pointed outin the appended claims.

My invention is illustrated in the accompanying drawings, forming partof this ap plication, in which Figure 1 is a side elevation of theClBVlCGIS applied to a fuse block or receptacle,

Figure 2 is a sectional view of my device, a portion thereof'being shownin elevation,

Figure 3 is a section along the line 33 of Figure 2, and

Figure 4 is a section along the line 44 of Figure 2.

In carrying out my invention, I make use of the ordinary type of fuseblock 1, such as found in the standard house lighting circuit. Thisblock 1 has a receptacle portion 2 of insulating material formedintegral with the block 11 A contact shell 3 is provided with rolledthreads adapted to receive a threaded portion of a fuse plug 4. The fuseplug 4 is provided with a fuse 5 extending from a contact point 6 to ametallic casing 7. A terminal post 8 is electrically connected to theshell 3. A terminal post 9 is electrically connected to a strip 10 whichextends beyond the center of I the block 1.

I provide a contact screw which consists of i a body portion 11, a cover12, a threaded-shank 13, a contact point- 14, and a fuse wire 15.

The body portion 11 and the cover 12 are discs formed of any suitableinsulating'material and provided withaligned recesses 16 and 16respectively. The threaded shank 13 is provided withintegral projections17 which are receivable in the recesses 16 and 16. De

pressed portions 18 and 19 are provided inthe body portion 11 and thecover 12, respectively, for forming a- :iTuse-rec'eiving compartn'ientwhen the body portion 11 and'cover 12 are in their assembled position.The fuse wire is substantially U-shaped and disposed in the compartmentin such a manner that one end thereof is rigidly secured to the threadedshank 13, and the other end rigidly secured to the contact point 14; Thebody portion 11 and the cover 12 may be secured together by any suitablemeans not shown.

From the foregoing description of the various parts of the device, theoperation thereof maybe readily understood. The threaded shank 13 may bescrewed into the block 1 and into. the strip or conductor 10. In thismanner, the contact screw may be removed from the front of the block.This may be prevented however if so desired by placing a lock nut 20upon the end of the threaded shank 13 adjacent the strip 10. The fuseplug 4 is then disposed in the shell 3, the contact point 6 engagingwith the contact point 14.

Let 'us assume that the fuse 5 of the fusecase of high amperage, thefuse wire 15 which is slightly larger and more durablethan the fuse 5will burn out.

I claim:

1. The combination with a fuse block having a fuse receptacle, a contactshell disposed in said receptacle, a terminal post in electricalconnection with said contact shell, a second terminal post, a fuse plughaving a metallic casing receivable in the contact shell, a centralcontact point, and a fuse connecting said metallic casing with saidcentral contact point, of a contact screw adapted to be di posed in saidcontact shell and in engagement- -with said central contact point, saidcontact I screw being in electrical connection with said second namedterminal post, and fusible means carried by said contact screw forbreaking the circuit between said contact shell and said second namedterminal post.

2. A device of the type described comprising a threaded shank receivablein a fuse plug receptacle, a body portion, a cover, a central contactpoint carried by said cover, and means for electrically connecting saidcentral contact point with sa d threaded shank.

3. A device of the type described comprising a body portion havingrecesses and a groove the *ein, a cover having recess and a groovetherein adapted to align with the recesses and groove of said bodyportion, a threaded shank, lugs integral with said threaded shank andreceivable in said recesses, a central contact point carried by saidcover. and a fuse Wire electric; lly conncctei to said central contactpoint and said threaded shank, said grooves in said body portion andsaid cover forming a COlilptlllllllefl l for receiving said fuse Wire.

4. A device of the type described 601111 ning a pair of insulatingmembers having grooves therein forming compartment :1 contactpoi-ntcarried by one oi. said insulatingmembers a threaded shank through theother of said insula inc bers, a projection integral Witn said shanl-tand receivable in one of said compartments, and means for connectingsaid contact point with said shank.

5. A device of the type described coni n'ising pair of insi'l'latinginenmers havingg'rooves therein 'l OI'IHlDQ roinpartnients a contactpoint carried by one of said insulating lnenib a threaded shankextending through the other i said insulating in hers, a projectionintegral with Khalil sh; and receivable in one of said eon'ipartinents,and fusible means for connecting said contact point with said shank.

ROY HEHRMAN VJILLIAMS.

